


And What, Pray Tell, Could Possibly Have Been Plan A?

by thunderpuffin429



Series: Plan A for Alpha [2]
Category: Supernatural
Genre: Alpha Dean, Alpha Sam, Alpha/Beta/Omega Dynamics, Alpha/Omega, Anal Fingering, Anal Sex, Birthday treat for Cas, Blow Jobs, Brief mentions of M/M/M threesomes, Dean and Sam are step brothers, Love Confessions, M/M, Marking, Mating Bond, Omega Castiel, Self-Lubrication, True Mates, college/high school AU
Language: English
Status: Completed
Published: 2016-07-29
Updated: 2016-08-15
Packaged: 2018-07-27 12:10:23
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 6
Words: 8,548
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7617580
Author URL: https://archiveofourown.org/users/thunderpuffin429/pseuds/thunderpuffin429
Summary: <blockquote class="userstuff">
              <p>Sam has gone off to college, disrupting the Winchesters' dynamic with their Omega, Cas. Dean takes Cas out to dinner for his birthday, and they enjoy each other's company without Sam much more than they had anticipated. Meanwhile Sam is at Stanford making new friends...</p>
            </blockquote>





	1. Chapter 1

**Author's Note:**

> Title courtesy of Crowley :)
> 
> So I took some liberties with the boys' ages for this one if you'll indulge me! This is how they are in my ABO universe...
> 
> Dean - Jan 24th 1981  
> Sam - May 2nd 1983  
> Cas - Jan 18th 1984
> 
> So it's Jan 2002 and Sam is a week off being 19, Cas is turning 18, and Dean is just about to turn 22.

“Hey, there's the nearly-birthday boy!”

Dean sat down at the table and smiled at Cas, who was making coffee, dressed in his boxers and Dean’s old AC/DC t-shirt.

“You excited about your surprise?”

Cas set two mugs of coffee down and sat opposite Dean.

“I think so,” he said. “I'm not very good at surprises.”

“You're gonna love it,” Dean stated confidently.  “I promise”.

He gave Cas a wink as he drank his perfect coffee. Damn, Cas could whip up a good brew.

Cas smiled at the gorgeous Alpha across from him.

It was still kind of strange in the house without Sam.

They'd driven him all the way to Stanford. One final road trip for the three of them before Sam started his law degree.

Cas had gone to visit his family in Sacramento while Sam took Dean on a tour round campus.

Cas hated lying to his parents, but he didn't think their hearts could take knowing that he was in a polyamorous relationship with two step-brothers. So he kept up the pretence that he and Sam were exclusive and betrothed and that his Alpha would be flying home to Kansas every weekend.

Mr and Mrs Novak weren't worried about Cas staying on his own with Dean during the weeks. As far as they were concerned, Dean was a responsible adult and would never take advantage of living with an unmated Omega. That was true; Dean would  _ never _ take advantage if Cas didn't want him. Fortunately Cas DID want Dean just as much as he wanted Sam - in every way and on every available surface.

Before Sam left, the three of them had a family meeting about what the agreement would be with regards to everyone's physical needs while they were apart.

“Look, I don't expect you not to touch each other until I come home,” Sam had begun. “I can't afford to visit all that often, and chastity isn't anyone's bag.”

“What about you?” Cas had asked. “Phone sex is only going to satisfy for so long.”

“And what about your ruts?” Dean had added. “You're gonna need us.”

In the end they'd drawn up a list of rules. Dean and Cas could fuck whenever, but try to involve Sam as much as possible with photos, videos and Skype. Sam could engage either one of them (or both) in a dirty text message conversation as and when he felt like it. Sam would come home for his ruts unless something important was going on at Stanford, in which case they would try to come out to him.

“What if you meet someone?” Dean asked, brow furrowing at the idea.

“To be perfectly honest, I doubt I'm going to have much time for a social life,” Sam replied. “My schedule looks pretty brutal.”

Dean was so proud of his step-brother/boyfriend/whatever the hell he was… But he was really sad to be losing him to college, and maybe also a little jealous that Sam would be experiencing a lifestyle that Dean never had a shot at.

For the first semester it had all worked pretty well. There had been plenty of Skype and FaceTime sessions, during which Dean and Cas would partake in some red hot sucking and fucking, and Sam would give them instructions while stroking himself furiously and hoping his roommate wouldn't come back any time soon.

On Halloween they'd Skyped him dressed as demons, wearing nothing but matching red silk underpants and devil horns. That had been a very quick call, because Sam had been on his way out to a party.

_ "Oh so you  _ do  _ have time for a social life, huh Sammy?!” _

When they'd called to wish him a happy thanksgiving it had been kind of sad, all wishing they could be together. But it soon descended into smut, with Cas describing down the phone how much he longed to feel both his Alphas’ dicks in him again.

_ “One in my ass and one down my throat… all night long…” _

When Sam had flown back for Christmas, Cas had been in heat and they hadn't even made it out of the airport. Sam had fucked Cas in the bathrooms of the arrivals lounge, holding him up against the door while Dean jerked off watching them.

During the holidays they could all sense the change though. No one mentioned it out loud, and they probably wouldn't have been able to describe it even if they'd tried, but something in their dynamic had shifted. They talked and laughed and fucked and cuddled like before, but it wasn't the same.

So now it was January. Sam was back in California and there were just two in the bed again.

Cas was eighteen tomorrow and Dean had decided to do something special for his Omega. 


	2. Chapter 2

Dean picked Cas up from school at lunch time, but still wouldn't tell him where they were going.

“Well, there are suitcases in the back so we must be staying overnight somewhere,” Cas deduced.

“Dude just stop trying to guess, and chill out,” Dean instructed.

“Are we going to Disneyland?”

“No.”

“Graceland?”

“No.”

“Dollywood?”

“Yes.”

“Really?!”

“No.”

Two Skynyrd albums later, they were in Lincoln, Nebraska, and Dean was pulling into the car park of a luxury hotel.

“Oh my god,” Cas said, wide-eyed. “Dean!”

“Pretty fancy, huh?”

The Impala crunched over the gravel.

“Fancy? Are you kidding? I think I just saw Bill Gates!”

Dean smiled. He’d chosen well.

“It must cost a fortune to stay here,” Cas said, worried.

“Yep,” Dean confirmed, pulling up the parking brake. “So we'd better go get our money's worth, your highness.”

* * *

Up in their suite, Dean adjusted his tie in the mirror while he waited for Cas to come out of the bathroom.

The new suit had been Cas’ other present, and the store had a deal on so Dean had treated himself to one too. It was a charcoal grey three-piece, and he'd teamed it with an ivory shirt and maroon tie. He was rarely in anything other than his work overalls these days, and he was enjoying the sight of himself like this. Dean wasn't particularly vain, but he knew when he looked hot, and tonight he looked fucking smoking.

Cas’ suit was navy blue with a matching tie and pale blue shirt. Dean chose it all specifically so it would compliment Cas’ amazing eyes.

“Dean, this suit is gorgeous!” the birthday boy called from the bathroom. “You shouldn't have spent this much on me!”

“Ah well, you're only eighteen once,” Dean called back, taming a lock of wayward hair. “Besides, if I wanna spoil you, I can and I will!”

The suite was even nicer in real life than on the website - King-sized bed, their own little bar, coffee maker, flat screen TV, whirlpool bath which they would definitely christen later… It had cost Dean nearly a month’s pay, and with the suits and gas money to get here as well he’d be lucky if they ate again before Easter, but the look on his Omega’s face had been worth every cent.

The bathroom door opened and Dean caught sight of Cas in the mirror before he turned around.

“Wow,” was his initial appraisal.

“It fits perfectly, thank you Dean,” Cas grinned, a little shy.

Dean made no attempt to hide the way he was greedily eying Cas up and down.

“You sure scrub up nice, Mr Novak,” he said, stalking towards Cas.

“You too Mr Winchester,” Cas returned with a coy smile and a slight bite of his bottom lip. “I’ve never seen you so dressed up. You look extremely handsome.”

“I feel like James Bond,” Dean confessed with a smug purse of his lips, as he reached Cas and ran his hands up the smooth navy blue sleeves.

“Please don’t do the accent.”

Dean bent down to inhale the scent of Cas’ skin, and Cas instinctively bared his neck to allow his Alpha access.

“ _Mmmm,_  you smell as good as you look,” Dean told him in a low voice. “Damn Cas, the things you do to me...” He sneaked his hands inside Cas’ jacket round to his lower back, and licked a little behind Cas’ ear.

“You’re getting me a bit, um, excited here,” Cas said, flexing his fingers at Dean’s shoulders. “We won’t make it to dinner if you keep doing that.”

“Whatever they’re making, it won’t taste as good as you…”

Cas laughed. “Come on Mr Bond, let’s go show off these suits.”

Dean groaned but conceded, and stepped back from Cas. He took in the sight again, then a thought occurred to him.

“Let’s send Sam a photo,” he reached to take his phone out of his pocket.

 _Sam._ Cas realised he hadn’t thought about Sam all day. In fact he’d barely thought about him at all this week.

Dean put his phone on timer, set it on the mantelpiece then moved to put his arm round Cas.

“Look sexy!”


	3. Chapter 3

The dinner was fantastic. Three courses including the most perfect steaks, and excellent wine. Neither of them had any frame of reference for the wine, it must be said, but it was red and smooth and yummy and that was enough. The staff treated them like royalty, and it wasn't bad for what technically amounted to their first proper date.

“This is so amazing,” Cas said.

Dean smiled and took another sip of wine. He paused as he felt his phone vibrate in his pocket. He took it out and smiled as he read the message out to Cas.

“It's from Sammy; ‘ _Y_ _ou both look gorgeous, have an awesome night guys’_.”

“Did he know you were doing this for me?” Cas asked.

“Yeah - I told him he should come but he couldn't get away.”

Cas nodded, wondering what was wrong with him that he was glad Sam hadn't been able to join them. He felt very disloyal.

“You know,” Dean said, placing his glass down and leaning forward conspiratorially on the table. “These last few months… I wasn’t expecting to enjoy it being just the two of us as much as I am.”

Dean sat back, holding Cas’ eyes with a small smile and Cas’ guilt lifted. Maybe Dean was secretly glad about Sam’s absence too.

Cas considered how his relationship with the boys had evolved over time. It had always been Sam with whom he’d had more in common - they were closer in age and shared a lot of the same interests and favourite authors, and they’d always had a lot to chat about. With Dean the talk was usually limited to pre-penetrative filth and dinner plans.

When they’d first got together, Cas had been sixteen, Sam a few months off eighteen, and Dean was twenty. Twenty is old if you’re sixteen, and Cas had idolised the elder Winchester. He was strong and broody and so damn sexy that Cas nearly passed out every time Dean touched him. Right from the start it was Sam who’d been Cas’ best friend, but it was Dean’s company that gave him the bigger thrill.

Since Sam had been at Stanford, the conversation between Cas and Dean hadn’t been nearly as stilted as Cas had feared. They discovered that they actually liked a lot of the same movies, and were equally partial to a good cheeseburger. They shared a similar sarcastic humour, and even without Sam, the sex between them was fiery as hell. Dean had also been very supportive when it came to Cas’ schoolwork, and even if he couldn’t directly help him with it, he was always on hand for a neck rub or a synapse-stimulating coffee.

The intimidation that Cas used to feel around Dean had steadily dissipated, and now there was no one on earth he’d rather spend his birthday with. Dean and Cas shared a zodiac sign, and in a few days Dean would turn twenty two.

 _Shit,_ Cas started panicking about what the hell he would do for his Alpha’s birthday that would come close to this. The ‘Serenity’ special edition dvd and classic Godfather PlayStation game he'd ordered suddenly seemed a little lame.

He snapped out of his worries and noticed that Dean’s expression had fallen a little. He was frowning down at the table, seemingly lost in thought.

“Are you ok?” Cas asked.

Dean flicked his eyes up. He cleared his throat and shifted in his chair.

“I was just thinking about Sam.”

“Oh,” Cas said. _Of course he’s thinking about Sam. He misses him. I’m not enough for him. I'm so stupid._

“Yeah,” Dean continued. “And how it’s not going to be long before I’m packing _your_ stuff up and driving _you_ to college.”

There was a pause.

“Then I’ll be all alone.”

Cas couldn’t bear the forlorn look on his Alpha’s face, and grabbed Dean’s hand across the table.

“I’ll go to school in Kansas,” he said hurriedly.

Dean snorted. “Yeah right,” he said. “You’re just as smart, if not smarter, than Sam. Hell you’ll probably end up in Harvard or Yale, or I’ll have to put you on a fucking plane to England so you can go to Oxford…”

A brief silence fell as they contemplated the idea of living apart.

“I don’t wanna go anywhere if you can’t come with me,” Cas admitted. “I’d rather stay in Lawrence and work at the Gas ‘n’ Sip.”

“Don’t be fucking ridiculous,” Dean said, knocking back some more wine. “You’re not wasting your life with me, stuck in a dead end job. We’re not mated Cas; you have no obligation to stay with me. You’ll go to college and meet another Alpha who’s actually going somewhere in life.”

“Don’t say that,” Cas stood up and walked round the table to kneel at the side of Dean’s chair. He put his hands on Dean’s leg.

Dean looked around them self-consciously, but it wasn’t unusual for Omegas to get on their knees for their Alphas during dinner, and the staff at the hotel had seen their fair share of powerful businessmen being ‘serviced’ during meetings. No one batted an eyelid at Cas’ actions.

“I don’t care that we’re not mated,” Cas said, gaze fixed upwards on Dean’s smouldering green eyes. “I love you. I wanna be with you, with or without Sam.”

Dean looked surprised.

“Without Sam?” he repeated.

Cas blushed, sure that he’d caused offense. Dean probably hated the idea of being without his step-brother.

“Well, yeah…” Cas stammered. “I mean… with Sam being away… I’ve still felt… I don’t know…”

“You said you loved having two Alphas.”

“Oh I do, it’s awesome,” Cas smiled. “But I’d be just as happy with one. If it were just you.”

Dean looked at Cas thoughtfully and licked his lips, looking a little nervous.

“What if it was just Sam?”

“What?”

“What if _I’d_ gone to college and you were left with Sam? Would _he_ be the one getting this speech instead of me?”

Cas put one of his hands on Dean’s cheek and shook his head.

“I don’t think so,” he said. “I love Sam but… I don’t know, it’s like… like you and I somehow share a more profound bond.”

At that moment the waiter appeared with their desserts.

“Gentlemen,” he said as he placed the dishes down.

Cas coughed and returned to his seat.

“Thank you,” Dean said, as the waiter nodded and made his exit.

“This looks delicious,” Cas observed, grateful for the distraction. He was mortified at the thought that he’d ruined his perfect birthday meal by blurting all that out and making Dean uncomfortable.

Cas lifted the spoon to his mouth, and hummed with pleasure as the chocolate and raspberry pavlova slipped past his tongue. He closed his eyes and licked his lips slowly; he’d never tasted anything like it. When he opened his eyes Dean was looking at him, amused and aroused.

“You can take the dessert back to the room if you want and I'll just go sleep in the car.”

Cas smirked, relieved that they were back on safe ground. “Jealous?” he teased.

“Me? Never…” Dean countered, and began to pantomime some fellatio on his spoon.

Cas’ cock perked up at the sight, and the remainder of the dinner was spent shamelessly flirting and performing lewd acts on their cutlery.

When dessert and coffee were done, and they were both virtually drooling with lust, they left the restaurant hand in hand, buzzing with anticipation.

The wait for the elevator was torturous, when all they wanted to do was get up to the suite and devour each other. A few other hotel patrons were waiting beside them. The boys smiled politely, knowing that their erections weren’t being very well hidden by their tight suit pants, but hoping no one would look.

Dean leaned close to whisper in Cas’ ear. “You look so fucking good in that suit…”

Cas shivered at the proximity of Dean’s lips and breath.

“...but I can’t wait to tear it off you.”

The elevator dinged and they stepped in, backing up to the far wall to let everyone else in. Behind the crowd like this, they were safe from prying eyes, and Dean immediately released Cas’ hand in favour of palming the Omega through his pants.

Cas bit his lip to keep from moaning, and kept his eyes front, knowing that if he looked at Dean he wouldn't be able to restrain himself. Slick had been leaking out of him since dessert, and now his ass was pretty soaked.

Dean leaned in to nose at Cas’ neck.

“Want you,” he whispered.

A whimper left Cas’ throat before he could police it, and the lady in front of them turned her head and coughed indignantly. Dean smirked and moved away, but not before licking up the side of Cas’ neck, causing him to tremble and bite his lip even harder in an attempt to keep himself together.

The elevator stopped on a floor which was not theirs, and the rest of the occupants disembarked. It could have been that they all just happened to be staying on this floor, or it could’ve just been that decency (or awkwardness) compelled them to leave the horny young men to it and walk the remaining distance to their rooms. Either way it made no difference to Cas and Dean, who were on each other the second the doors closed.

Dean pushed Cas against the mirrored wall as the elevator set off again, and kissed him, fevered, fingers in his hair and the front of one thigh between his legs.

Cas made a desperate sound and grabbed Dean’s ass with both hands, as Dean changed tactic and went for Cas’ neck again, only interrupting the kissing and licking long enough to mutter some filth in his Omega’s ear.

“Want you so bad Cas… wanna fuck you all night long… wanna be inside you for hours and hours… I’m gonna make you come so hard baby…”

“Oh _Dean_ …”

The elevator finally got to their floor and they made their way along the blessedly empty hallway, groping and kissing each other the whole time. At the door to their room, Dean scrabbled with the key card while Cas stood pressed up behind him kissing his neck, and rubbing the Alpha’s throbbing dick through his pants.

Dean’s predatory primal side caused him to release a low growl in his throat, the sound of which induced another wave of slick to pour out of Cas, and they barely got inside the room before they were pulling at each other’s suit jackets and fumbling for each other’s flies.

The frantic activity screeched to a halt as the never-sexy task of removing shoes became a necessity, but they soon resumed course, hungrier for each other than they’d ever been. Grabbing and mouthing at each other, they made a chaotic path over to the bar, clothes in disarray and breath coming out in wild pants. Cas nudged Dean up against the shiny wood, tucking him between the two leather-seated bar stools. Dean let himself be pushed, content to yield a little control now and then, and let Cas remove his belt and unzip his fly.

Having tugged the grey suit pants down to Dean’s ankles, Cas licked his way up the inside of one of his legs, and Dean groaned at the sensation of Cas’ hot tongue on his skin.

Too impatient to be teased, Dean put his thumbs underneath the waistband of his boxers and lifted them over his raging erection. Cas took the hint and slid them all the way off, licking and kissing Dean’s muscular legs all the way down. Dean stepped out of them and the pants, and Cas ripped off Dean's socks as well while he was down there. Crouched on the floor, Cas looked up at his now half-naked Alpha. The sight of Dean’s cock at full mast literally made Cas’ mouth water, and it took him precisely one and a half seconds to kneel up and get his lips around it.

“Aaaaah!” Dean grabbed hold of the back of one of the stools to steady himself as his dick disappeared down Cas’ throat.

Cas was a fucking genius at giving head, and he had many different methods in his repertoire. Tonight was all about the classic deep-and-dirty, and he sucked up and down Dean’s cock while fondling the Alpha’s balls.

“Fuck, _fuck,”_ Dean was already losing it, and the knowledge went straight to Cas’ own unattended erection. “Cas… shit… Cas I’m so fucking… _aaahh_ _Cas!_ I’m close… Shit… _Fuck…!”_

With all the build-up it was no surprise that Dean was ready to blow, and Cas brought out the big guns for the grand finale. He worked his way up Dean’s shaft with a kind of tooth-free chewing motion, then very _very_ lightly nibbled at Dean’s frenulum as he stroked Dean firmly from base to bell. Dean screamed as his knot swelled, and Cas squeezed his balls as he took the Alpha all the way into his mouth once more. Dean arched away from the bar as he started to come. Cas pulled off a little so that he didn’t choke for one thing, and also so that he’d get come all over his face, the sight of which he knew Dean loved. Dean was always a sucker for a porn-star finish.

True to form, Dean was looking down at Cas’ messy features with a look that was simultaneously impressed, exhausted, horny and a little smug.

“Get up here…” he panted.

Cas rose, licking the come from around his mouth, and wiping his chin with the back of his hand. He took in the sight of Dean leaning there with chest heaving, shirt creased, three buttons undone, tie all crooked and hair totally mussed… and Cas couldn't get over how beautiful his Alpha looked like this.

Dean put one hand round the back of Cas’ neck, and pulled him close. Dean’s other hand went straight down Cas’ open pants to grab his cock. Their foreheads rested against each other as Cas gripped Dean’s shoulders and sighed with relief.

 _“Oh…_ oh _yes_ …”

“I've got so many plans for you tonight, baby,” Dean murmured. “We're just getting started…”

Dean jerked Cas off fast and filthy, and Cas couldn't find it in him to be embarrassed about the speed with which he was approaching orgasm. Knowing that this was only round one sent a shiver of anticipation up his spine, and he came in Dean's experienced hand with a gasp.

Cas put his head down on Dean's shoulder as he shivered his way down from climax. Dean tilted his face to kiss Cas’ neck, and fought back the urge to bite, to claim. _Mine…_ he couldn't help thinking. _Mine…_

Shoving that desire away for now, Dean lifted Cas’ head up and playfully licked the end of his nose.

Cas scrunched his face up in mock disgust and swatted Dean in the tummy.

Dean chuckled. “You know…” he said, pulling Cas in as close as possible. “I've paid for a whirlpool bathtub, birthday boy. We should go get our money's worth!”


	4. Chapter 4

The whirlpool bath sure went well with the bottle of Champagne that Dean liberated from their bar. And the bubbles in the water (as well as in their glasses) _definitely_ added an extra layer of pleasure to all the rimming and stroking that was going on.

Dean was determined to give Cas the most amazing birthday experience he could, and that was damn well going to include as many orgasms as possible.

The few weeks after Sam left, Dean had felt extremely bereft without his first love. The Winchester boys hadn't been apart for more than a few hours in five years, and it was a huge adjustment. Dean drew comfort from Cas; enjoyed his company in the day and his body during the night, but Dean found he couldn't come unless he pictured Sam’s face.

But then he and Cas started to talk more, and spend more quality time together. Cas made Dean genuinely laugh out loud a lot, and he had some really interesting opinions that Dean enjoyed hearing. Cas was very smart, which made him even sexier. He also apparently liked sci fi movies and video games, so home date nights became a lot more than just screwing.

Although, there was still a hell of a lot of screwing.

And then one day Dean stopped imagining that Sam was there with him when he fucked Cas. Without warning he just stopped needing visions of Sam’s chest and cock to help get him to the edge. He only needed Cas. Cas, and his beautiful piercing eyes. Cas, and his stunning body and heavenly scent. Cas, and his unabashed screams of ecstasy. Cas, and the way he kissed Dean like it was the last thing he'd ever do on this earth. Cas, Cas… just Cas.

Bath time over, Cas was back in the bedroom and Dean was brushing his teeth. Cas had been unable to fight his compulsive need to tidy, and had rescued all the strewn clothing on his way through the suite. He was now perched on the King-sized bed waiting for his Alpha. His heart was thumping and he didn't want this night to end.

Dean smiled at the neatly-folded suits stacked on the leather couch, before heading into the big beautiful bedroom.

He stopped at the doorway to take in the view of a totally naked and still slightly damp Cas sitting on the end of the bed. Dean shook his head as if he couldn’t believe the sight in front of him and bit his lip.

“Cas,” he smiled. “Gorgeous little Castiel Novak from next door…”

Cas blushed, frowned and smiled all at once, as Dean started to walk slowly towards the bed.

Cas took a shaky inhale and his eyes darkened as he watched Dean stalk towards him.

Dean let his towel slide off as he reached his Omega. Cas looked up at his face with awed desire, and Dean stopped in between his spread legs. He put his hands on Cas’ cheeks and bent down to kiss him. One long, affectionate kiss on those beautiful full lips. Dean hummed his appreciation and kept his eyes closed as he pulled his face away. When he opened them again, Cas was looking at him with tears in his eyes.

“Hey,” Dean said, concerned. “What’s wrong, baby?”

“Nothing,” Cas breathed. “I’m just…”

He stopped himself, not wanting to be sappy but really wanting Dean to know the truth.

“Just what?” Dean prompted.

Cas took a deep breath and looked into Dean’s eyes.

“I just love you so much,” he said quietly. “It’s overwhelming.”

Dean smiled and stroked Cas’ hair away from his eyes. 

“Cas…” Dean began, but he abandoned that sentence in favour of laying a soft passionate kiss on his Omega’s lips.

As they kissed, Dean gently pushed Cas back down onto the bed, and Cas instinctively wrapped his legs around Dean’s bare waist.

Dean’s dick had clearly decided it was ready for the next act, and Cas could feel it pressed up against his thigh.

“Oh god, you're so hard,” Cas said brokenly into Dean’s ear. His arousal was generating so much slick; he pitied the hotel chamber maids who would be obligated to deal with the aftermath.

“It's all for you sweetheart,” Dean murmured as Cas rolled his hips under him. “All just for you baby boy. I'm all yours.”

Cas moaned and kissed his Alpha deep and slow as more slick ran out of him. Then he whispered into Dean's ear as Dean licked at his jaw. “Do you know what I was thinking today?”

“What's that, baby?” Dean drawled in between kisses and licks.

“I'm so glad that it was, um, _you_ who took my virginity,” Cas answered, shyly, running his hands up Dean's arms.

Dean pushed himself up on his forearms and looked down at Cas, quizzically.

Cas elaborated; “I know I had you both that night, but - you were the first.”

Dean smiled and stroked a thumb down Cas’ cheek. “Yeah, yeah I was.” He ducked down to gently kiss at Cas’ clavicle. “Is that important to you, sweetheart?”

Cas clutched at the sheets by his sides, always reduced to a wild mess when Dean was tender and slow with him.

“Yeah,” he breathed, tightening his legs round Dean’s waist. “It's important. Makes me… yours.”

Dean hummed low in his throat, and put his hand down between their bodies to steer himself into his Omega. Cas loosened his hold a little to aid Dean's progress, and lifted his thighs even higher. His skin was tingling all over in anticipation of feeling Dean inside him.

Dean gently pressed in and Cas rocked his head back onto the pillow.

“Oh Dean,” he gasped. “You always feel so fucking good.”

Dean fucked Cas deep and slow, and there was only the sound of their breathing and soft cursing for a while. It occurred to Cas, amid all the searing pleasure, that it was unusual for Dean to be so quiet. He normally loved talking dirty, and showering erotic praise on his little Omega. Cas worried that something was wrong. He was holding on to Dean's shoulders and Dean’s face was buried in his neck.

“Are you okay?” Cas asked softly.

Dean raised his head and looked into Cas’ face. Dean’s green eyes looked kind of distant and - moist.

“Dean?”

“I…” Dean stammered. “I think about you all the time.”

Cas frowned, wondering if Dean meant that as a good thing.

“Even when I try to distract myself, I can’t - stop - thinking about - my Cas…”

Dean was still sliding up and down inside Cas so gently, and the sensation combined with Dean’s soft emotional voice was sending Cas to the stars.

“The way you laugh, the way you walk, the sounds you make in your sleep, how you look right before you come…”

A sobbing sound left Cas’ mouth, and his back arched as he felt his climax bounding towards him.

“I, I'm just…” Dean’s voice and body were shaking, and his voice dimmed to a whisper. “I'm so in love with you, Cas.”

“Aaaah, _Dean!”_ Cas cried. “Oh my god!”

They said 'I love you' all the time, but _in love_ is a whole different ball game, and Cas' soul soared at Dean's sweet confession.

Cas was on the unstoppable slide down into orgasm, and he wanted desperately to feel something else as well as it happened. 

“Dean,” he begged, breathless. “ _Bite me.”_

The Alpha in Dean released a deep and impassioned growl. “Are you sure?”

“Mo- more than I've ever been about anything.”

Dean nosed at Cas neck, scenting out the mating point.

“Please, Dean, _please,_ I'm gonna come…”

Dean thrust deep and hard into Cas, as he sunk his teeth into his flesh. Cas screamed as he came between their bodies, and his ecstasy was infinitely and immeasurably intensified by the feel of that bite.

“Dean! _Dean!_ M- my Dean… my Alpha!”

Dean released Cas’ neck as his knot caught inside his Omega - _his_ Omega - and he came harder than he'd ever come in his life.

“Cas! Cas, oh my god, Cas, _fuck…!”_

Dean's body shuddered through his climax and they both trembled with the aftershocks for a while. Then it all got very still and quiet. Dean laid gentle, barely-there kisses on Cas’ neck and throat, while Cas swirled delicate shapes over Dean’s sides with his fingertips.

When Dean sensed that his weight was probably getting too much for Cas, he rolled them both over carefully, legs intertwined, knot buried deep.

They gazed into each other’s eyes, dopey and happy and totally spent.  

Cas reached to place a kiss on Dean's lips; something that he could happily do every minute of every day for the rest of his life.

“Best birthday present ever,” he murmured, and Dean smiled.

“You meant all that, right?” Cas asked, suddenly worried. “That wasn't just the Champagne?”

“I meant every word, baby boy,” Dean said, softly. “Okay yeah, the vast amount of alcohol we've had tonight probably helped me find the balls to finally say it out loud… but I mean it, I promise.”

Cas flooded with relief, and he put his hand up to feel the mark Dean had left on his skin.

“We're going to have some explaining to do,” he said.

Dean pulled him close and wrapped him in his arms. “Don't worry about that now,” he said. “Just sleep, baby. I've got you.”

 

 


	5. Chapter 5

They left their luxurious room about a minute before they were scheduled to check out; Dean determined to get every cent’s worth. Only when he was satisfied that they had drunk enough complimentary coffee, watched enough wide-screen cartoons and defiled enough furniture did they leave.

The drive back to Lawrence was pretty quiet. Dean and Cas were both dealing with a strange cocktail of emotions after their night. Cas was thrilled and so proud to be wearing Dean’s mating mark, but he felt terrible when he thought of how much it might hurt Sam. Despite the passion Cas once felt for the younger Winchester burning out, Sam was still his best friend and he loved him very much. He had been his knight in shining armour last year too, defending him from a potentially extremely damaging Alpha attack at school, and mating with Dean behind his back was hardly a fitting way to repay him. Guilt swept over Cas and an audible sigh escaped him as he sunk a little lower in his seat.

Dean reached over and grabbed his hand, knowing exactly what the problem was.

“It’s ok,” he said, without taking his eyes off the road. “We’ll call him as soon as we get home and just explain, ok?”

“Do you think he’s going to be mad?”

“I don’t know,” Dean admitted, and returned both hands to the wheel.

A thought occurred to Cas. “Do you, um. Do you still want him - involved?”

Dean’s brow furrowed. “No,” he said, as if he were just realising it. “No I don’t any more, Cas. I mean damn I love him to death but it wouldn’t feel right any more. You and me - _that_ feels right.”

Dean glanced at Cas.

“Do _you_ still want him involved? I mean you’ve been used to two guys all this time…”

“Yeah I‘ve been pretty spoiled,” Cas agreed, with a soft chuckle. He put his hand on Dean’s leg and looked into the side of his face. “But I think you’re more than enough for me, Dean.”

Dean smiled, shot Cas a wink, and flicked the volume up on the stereo as they crossed the state line.

* * * * * *

They’d just finished unpacking, and were sitting in front of the desktop with coffee in their hands, trying to work up the courage to call Sam, when the familiar tone of an incoming Skype call took the matter out of their hands.

“Shit,” Dean flustered, running a hand through his hair.

“Everything’s going to be fine,” Cas offered, not very convincingly.

Dean took a calming breath and accepted the call.

Sam's cheery face appeared on the screen. He was sitting cross legged on his bed, talking into his laptop.

“Hey,” he smiled, with a small wave. “Hey guys.”

“Heya Sammy,” Dean said, really pleased to see the guy, despite dreading the conversation that was about to take place.

“How was your birthday Cas?”

Cas coughed nervously. “Great, thank you,” he answered. “It was… yeah, it was great.”

“Good, good… So listen, um… Kinda need to talk to you both about something.”

“Everything ok?” Dean asked, cautiously.

“Uh yeah, I just… I need to, um…” Sam shook his head and huffed a small nervous laugh. “I guess I gotta - break up with you. Both.”

Dean and Cas looked at each other.

“You gotta - what?” Dean asked. “How come?”

“Um… I met someone,” Sam blurted out, eyes flicking up to see how his news was being received. Dean and Cas were just staring at him in silence, so he took a deep breath and got it all out.

“I actually met her my second day. She’s in all my classes and she went to high school with the guy I’m sharing my dorm with.”

“And she’s a _she?”_ Dean cut in.

“Yes.”

Dean tucked his lips in and rolled them out slowly, nodding. “Ok... cool. Go on.”

Sam sighed. “So anyway, we got to talking and really hit it off. We were just friends, at first, I never really thought any deeper of it than that. We just hung out all the time and studied and laughed and talked and it was really easy and fun, you know?”

Sam glanced up at the two expectant faces on his screen, one slightly stonier than the other, before continuing.

“We were having dinner together one night and she was telling me about her ex - some douchey Alpha who’d been a total jerk and cheated on her with like three Omegas, and cause she’s a Beta she couldn’t smell them on him immediately and he just got away with it for months.”

The anger in Sam’s voice was evident.

 _Wow, he’s clearly already pretty possessive of this chick,_ thought Dean.

“I took the opportunity to tell her all about you two and our relationship. I thought she would think it was weird and judge me and stuff but actually she was really cool. She said the world is changing, and people should be allowed to form whatever family units and relationship dynamics that they want.”

“She’s smart,” Cas smiled, then recoiled a little at the look Dean shot him.

“Then…” Sam went on. “Then Halloween happened. She, uh, she invited me to a party and I wasn’t gonna go cause I knew I had a FaceTime date with you guys, but she insisted and I said I would go along later.”

“I remember,” Dean dead-panned.

Sam looked a little sheepish as he brushed past his step-brother’s remark. He continued his story, and whether it was down to nerves or excitement, he was rattling through his words at a hundred miles an hour.

“I went to the party and it was really fun. At the end of the night we were all kind of merry, and Jess and I were sitting on the edge of the pool just dangling our feet in and talking. There’d been this Omega girl who’d been trying to flirt with me all night; telling me how good I smelled and asking me over and over how I wasn’t already mated. I’d managed to shake her off and I was telling Jess about her. She was laughing and she went; ‘Poor girl, she’s really barking up the wrong homosexual tree, huh?’ so I corrected her, told her I was actually bi, and that technically I could’ve done something with that girl if I’d wanted cause I’m not mated, just committed, but also the only Omega smell that does it for me is Cas’...”

Cas flushed a little.

Dean rolled his eyes; “Take a breath, Sammy,” he instructed, but it was quiet enough that only Cas heard it.

Sam carried on at top speed. “I looked at Jess and she was just kinda staring at me with this look and it went really quiet and she kept just looking at me and then she leaned toward me and…”

“And she kissed you?” Cas interjected, eyes wide like he was watching a romantic movie.

Sam met his gaze, then looked at Dean.

“Yes.”

Sam’s stream of consciousness ended, and when he spoke again it was slower and considered.

“And I was stunned and frozen for a second, but then I kissed her back.”

Dean shifted uncomfortably in his chair. This news could potentially get him and Cas off the hook, but he still felt jealous at the idea of Sam being romantic with someone else. Better a Beta girl than another Alpha guy though. At least this way the answer to the worry of _what do they have that I don’t have_ was pretty clear.

“I could blame the alcohol I guess,” Sam went on. “But the truth is I really wanted her in that moment, and honestly it took a lot of will power to stop there. I was so - conflicted in the weeks after. We did a lot of talking and we were both pretty confused I guess. I felt so guilty about cheating on you guys, so I told her we had to just be friends again. She said the thought made her heart hurt a little - those were her exact words - but she said she still wanted to be my friend. I wanted to tell you when we spoke on Thanksgiving but we kinda got… distracted… so then I decided I would confess when I got home at Christmas instead, but damn Cas - you in heat kinda eclipses every logical and rational thought in my body and I just…”

There was a stiff lull as Sam tailed off and they all thought back to the Winter break, to the signs Dean and Cas totally missed.

“It wasn’t the same,” Sam said, quietly. “ _We_ weren’t the same over Christmas and it was my fault. I thought about Jess a lot, and I tried to tell myself I didn’t really wanna be with her, that it was just the novelty… Then I got back to college and saw her, and I just knew.”

He looked up again.

“I’m sorry.”

Dean and Cas looked at each other.

“Sam…” Dean began, voice low in volume and pitch. “It’s ok, man. I mean, I’m surprised and I wish you’d told us as soon as you caught feelings for her, but… it’s ok.”

“Really?”

“Yeah, really,” Dean took a deep breath. “In fact, while we’re confessing to shit, we’ve got one for you.”

“Oh yeah?” Sam’s brow furrowed.

Dean looked at Cas, who was chewing on his lip nervously.

“Show him,” Dean said with a small smile.

Cas looked at Sam, and tugged down one side of his high-necked sweater.

When Sam realised what he was looking at, his eyes widened and his jaw slackened.

“Wow,” he said on an exhale. “Ok…”

“We didn’t plan it,” Dean explained, quickly. “We didn’t even realise it was on the cards until it - was.”

Sam smiled. “I think _I_ could’ve told you it was on the cards,” he said.

Cas frowned. “What do you mean?”

“Oh Cas, you never looked at me the way you look at Dean,” Sam said, no trace of bitterness at all in his voice.

“But - I…” Cas started to stutter.

“It’s ok, man,” Sam lifted his hands. “There was a lot of love all round, I know that. And damn we all had a fucking _great_ time together... But there was an extra - _something_ \- between you two that I could never explain. I get it now, though. _Now_ it all makes perfect sense.”

Dean and Cas exchanged brief eye contact and Cas blushed.

Dean coughed.

“Uh, Cas,” he said. “Is it ok, um, if I just…” he indicated the screen, and Cas got it.

“Sure,” he said, hurriedly, getting up from his chair. “I need to run to the store anyway.”

Cas lingered for a moment, then looked at the screen. “I’m really glad you’re happy, Sam,” he said. “I’m sorry if you feel betrayed.”

“Not at all,” Sam smiled. “Love you man!”

Cas beamed. “Love you too!”

He bent down to give Dean a quick kiss on the temple then left them to it.

Dean watched him go, fondly, then turned his attention back to the man he once thought he’d be with forever. He found that words were not forthcoming, though. He wasn't actually sure what he wanted to say, just that he had to say something. Fortunately, Sam broke the silence for him.

“So… mated, huh?” he smiled. “And all the single Omegas of Kansas let out a collective wail of despair as Dean Winchester is finally claimed!”

Dean chuckled. “Bitch,” he said, affectionately. There was a slight pause. “You're not mad? Even a little?”

Sam shook his head.

“You guys were made for each other,” he said. “It was only a matter of time.”

Dean cursed his inability to speak under pressure. He wished he had access to a big vocabulary, like Sam and Cas. He just wanted to acknowledge the end of an era and articulate the ambivalence he felt at the change in his and Sam’s relationship. But he couldn't. He dropped his head and his frustration was evident.

“Dean,” came the voice from the screen. Dean looked up and met Sam’s eyes.

Sam smiled. Cas might be his brother’s true mate now, but he’d still known Dean the longest and could read every little facial tic and unspoken mood change. He knew what Dean wanted to say, because he felt exactly the same.

“Dean,” he repeated. “You were, and always will be, my first love.”

Dean’s face softened and his shoulders un-tensed.

“You made me feel things,” Sam went on, “That I’d never imagined, and you got me through the most painful time in my life. You’ve been my best friend, my boyfriend, my brother - even though that sounds kinda weird now - and there will never be a day when I don’t need you.”

Dean swallowed. “There’ll never be a day that I’m not here for you man,” he said, sounding choked.

“I know,” Sam smiled. “But you know, I think that even if I hadn’t met Jess... I think I still woulda made this call”

“Oh yeah?”

“Yeah. I love you, and I love my home but I just gotta go, you know?”

Dean nodded. He did know. Sam didn’t belong in a small town, never did. He was destined for great things and Dean couldn’t be prouder of him.

However, the moment was becoming just a little too saccharine for Dean’s tastes so he took a swig of his coffee and did what he did best - deflect emotions with comedy.

“I don’t know though man,” he said, faux-serious. “I’m worried that you’re gonna miss me too much. You sure your dick can cope with the downgrade?”

Sam raised an eyebrow, though he knew he was just being teased.

“I mean; two hot guys all on you all hours of the day,” Dean said, shaking his head. “...and now just one vanilla Beta chick…”

“Oh she is _not_ vanilla,” Sam asserted. “She’s, uh, well I’ll just say she’s got some interesting plans for me, if her messages are anything to go by...”

Dean grinned. “Glad to hear it.”

“But if it makes you feel better,” Sam said, a little flirty. “I have a whole stash of Dean-related porn in my brain that I don’t doubt I will call upon every now and then.”

Dean raised his coffee mug in salute. “Excellent news.”


	6. Epilogue

"Fuck! Yes, yes, Dean, fuck!!”

Cas was naked from the waist down, half-sitting on his new desk, cock down Dean's throat and hand in Dean's hair.

He came with another yell of Dean’s name, and Dean licked him clean. Then Dean stood up, put his arms round his Omega and kissed his neck.

“I gotta go to work now, baby,” he murmured.

“Nooo,” protested Cas, wearily.

“Yes,” insisted Dean. “And you've gotta get to class.”

Cas slid off the desk that Dean had made for him and went on a hunt for his pants.

They'd moved to Connecticut six months ago. They'd found a tiny little studio apartment which was absolutely perfect for them. It was walking distance from Yale and a short drive away from Dean's new place of work; Turner Classic Cars. Bobby had hooked him up with an interview with a guy named Rufus, who restored and reconditioned old cars. Dean nailed his probation period and was now working for Rufus full-time.

Dean and Sam retained ownership of their old home in Lawrence, and were currently leasing it to a cool older couple called Jessy and Cesar.

Pants retrieved, Cas stopped at the mirror and tried to tame his just-been-fucked hair.

“There’s a pointless exercise,” Dean teased. “Not enough gel in the world, baby.”

He put his arms round Cas’ waist, kissed his neck and looked at him in the mirror. “Your hair’s as sexy as you are and just as difficult to keep straight…”

Cas giggled and turned round in Dean’s arms. He kissed his Alpha deeply, and gave his cock a playful squeeze.

“Hey now,” Dean warned. “Don’t get started up again or we’ll never leave this room.”

Cas grinned a naughty grin. “Now _that’s_ a great plan.”

Dean shook his head. “I have a better one. Go get your degree.”

Cas sighed. “Fine.

He picked up his bag and laptop. “Are Sam and Jess still coming this weekend?”

“Sure are,” Dean said, grabbing his keys and hustling Cas out the door. “I promised him we'd keep the salacious stories to a minimum.”

“From what I gather she's rather keen to hear them,” Cas laughed, his voice echoing in the stairwell. “The more salacious the better!”

“Filthy and beautiful,” Dean chuckled. “She'll fit right in to this ridiculous family.”

“Did you just call me ridiculous?” Cas frowned.

“And _beautiful_ ,” Dean appeased, stopping at the bottom of the stairs to give Cas a farewell kiss.

“Go be brilliant, little Omega,” he said fondly as he headed out to his car.

“You too, little Alpha,” Cas smiled.

As Cas walked down the street, he felt compelled to send a silent prayer of thanks up to whichever omnipotent deities happened to be listening. He had his dream man, he was studying at his dream school, the sun was out and his best friend was coming to stay. He wasn't an idiot; he knew life had its ups and downs, and uninterrupted bliss would likely not stay uninterrupted. But, for right now at least, everything was perfect and he was so grateful.

A grey car sat parked across the street from where Cas was walking. Inside the car, a man was watching the Omega through designer shades.

As Cas disappeared round the corner, the man turned the ignition key and pulled slowly away.

 

**Notes for the Chapter:**

> I've left myself with a cliff hanger for the next part, even though I'm not entirely sure at this stage where I'm going with it lol Just wanted to make sure I'd be back cause I like these guys :)


End file.
